In general, a “frozen dessert” is defined as “frozen or chilled confectionery such as jelly, ice cream and sherbet” (Kojien, fourth edition, Iwanami Shoten, 1991). In the present application, however, a ‘frozen dessert’ is defined as follows.
That is, the ‘frozen dessert’ in the present application is broadly classified into “hard ice cream” and “soft ice cream” as shown in Table 1.
The “hard ice cream” is a frozen dessert which is in the form of an end product obtained through a ‘hardening process’ in a production flow to be described later and which is distributed while in a frozen state at approximately −20° C., and placed in a freezing cabinet and sold as a commodity at a store (commercial product). The “hard ice cream” is categorized into “ice creams” and “ice confections”.
The “soft ice cream” is a frozen dessert which is commonly called soft-serve ice cream and which is not distributed but is made with a frozen dessert production apparatus without a ‘hardening process’ in a store and sold at the store face to face to consumers as a prepared food product at approximately −4 to −10° C. directly taken out of the frozen dessert production apparatus. The “soft ice cream” is also categorized into “ice creams” and “ice confections”.
Furthermore, under the hard ice cream and the soft ice cream (hereinafter, abbreviated as soft cream), the “ice creams” are categorized into an ice cream standard, an ice milk standard and a lacto-ice standard based on the standards for ice creams specified under a ministerial ordinance according to their compositions such as milk.
Likewise, under the hard ice cream and the soft cream, the “ice confections” refer to frozen desserts containing less than 3% of milk solid. The ice confections are further categorized into fat-containing ice confections and fat-free ice confections as shown in Table 1.
It is noted that some products analogous to soft cream have been recently offered to consumers, which are a frozen dessert put in small-sized containers and distributed in the same manner as in the hard ice cream, and then forcibly defrosted in a dedicated defrosting chamber in a store until it is −8 to −12° C., extruded while each container is compressed and deformed with a dedicated extruder and served in a well-known soft cream form (twisted high). However, these products shall be categorized into the hard ice cream since they are obtained through a hardening process and they are distributed at −20° C.
TABLE 1FrozenHardIce CreamsIce Cream StandardDessertIce Cream(Milk Solid: ≧15.0%,Milk Fat: ≧8.0%)Ice Milk Standard(Milk Solid: ≧10.0%,Milk Fat: ≧3.0%)Lact-ice Standard(Milk Solid: ≧3.0%)Ice ConfectionsFat-containing(Milk Solid: <3.0%)Ice ConfectionsFat-free Ice ConfectionsSoftIce CreamsIce Cream StandardIce Cream(Milk Solid: ≧15.0%,Milk Fat: ≧8.0%)Ice Milk Standard(Milk Solid: ≧10.0%,Milk Fat: ≧3.0%)Lact-ice Standard(Milk Solid: ≧3.0%)Ice ConfectionsFat-containing(Milk Solid: <3.0%)Ice ConfectionsFat-free ice confections
Consumers may eat the hard ice cream at the point of sale immediately after the purchase, or may take it home by maintaining its frozen state with dry ice or the like, keep it in a freezer and eat it at an appropriate time. Since the hard ice cream immediately after it is taken out of the freezer is frozen very hard, the hard ice cream is generally eaten after the temperature of the product is approximately −10° C., at which it is soft enough to eat, and it thaws of its own accord by leaving it at room temperature.
However, the thawing time taken until the hard ice cream is soft enough to eat varies greatly depending on the surrounding environment. As time goes by, the surface of the hard ice cream may start melting earlier than the other part and impair a pleasant dry feeling, or an edge portion of the hard ice cream twisted high into a sharp and beautiful shape may run down and damage the shape, or the hard ice cream may melt and fall like a snowslide. Thus, consumers often miss the timing to eat the hard ice cream while it is in an ideal state.
When a small child or an elderly person who cannot quickly eat up a frozen dessert which is cold as being below zero encounters the above-described situations, the frozen dessert starts melting completely and dirties their hands or clothes, or melts and falls like a snowslide and drips onto the floor. Such situations are often observed.
The same is true of soft cream which is made at the point of sale without a hardening process, served on an edible container such as a cone cup and sold face to face while in a soft state at approximately −4 to −10° C. Consumers eat the soft cream in or around the store while holding the container such as a cone cup. Then, the soft cream melts with time and dirties hands and clothes of the consumers, or even worse the soft cream melts and falls like a snowslide and drips onto the floor, necessitating cleaning. Such situations occur more often when the ambient temperature is high, in particular.
In these frozen desserts, which melt with time unless they are kept in a frozen state as described above, maintaining a pleasant dry feeling by delaying start of melting as much as possible, maintaining a beautiful shape by delaying melting and falling as much as possible and maintaining a beautiful appearance perceptually appealing attractive taste (reinforcing shape retention for holding a predetermined shape) lead to improvement of product's value (product's life) and thus are very important objects as well as other properties such as flavor and texture.
As a conventional method for the reinforcement of the shape retention of frozen desserts, addition of a stabilizer and an emulsifier is known. Examples of the stabilizer include hydrophilic polysaccharides extracted from seaweed, vegetable seeds, microorganisms or the like; insoluble polysaccharides such as microcrystalline cellulose; and synthetic stabilizers such as carboxymethylcellulose (CMC). Examples of the emulsifier include low HLB emulsifiers such as unsaturated fatty ester.
In addition, Patent Document 1 reports that use of microcrystalline cellulose, carrageenan and waxy corn starch as stabilizers allows enhancement of the liquid stability of a liquid soft cream mix before the freezing and achievement of soft cream having good shape retention and superior drip resistance after the freezing for a long period of time. Here, it should be noted that microcrystalline cellulose is clearly distinguished from microfibrillated cellulose used in the present invention to be described later (see Patent Document 2, for example).